[GoldFinch]

Перехват UNetworkHandler::AddNetworkQueue, для фришек

#include <Windows.h>

class UNetworkHandler {};

#pragma pack(push, 1)
struct NetworkPacket
{
    unsigned char id, _padding1, exid, _padding2;
    unsigned short size, _padding3;
    unsigned char* data;
};
#pragma pack(pop)

int (__fastcall *UNetworkHandler_AddNetworkQueue)(UNetworkHandler*, int, NetworkPacket*);

int __fastcall UNetworkHandler_AddNetworkQueue_hook(UNetworkHandler* This, int /*edx*/, NetworkPacket* packet)
{
    // Полезная нагрузка перехвата
    char buf&#91;1024];
    wsprintfA(buf, "Packet id=0x%x, size=0x%x", packet->id, packet->size);
    OutputDebugStringA(buf);
    //-----------------------------------------
    return (*UNetworkHandler_AddNetworkQueue)(This, 0/*чтоугодно*/, packet);
}

DWORD WINAPI InitThread(LPVOID)
{
    HMODULE hEngine = LoadLibraryA("Engine.dll");
    (FARPROC&) UNetworkHandler_AddNetworkQueue = GetProcAddress(hEngine, "?AddNetworkQueue@UNetworkHandler@@UAEHPAUNetworkPacket@@@Z");
    void** UNetworkHandler_vftable = (void**)GetProcAddress(hEngine, "??_7UNetworkHandler@@6BUObject@@@");
    while(*UNetworkHandler_vftable != (void*)UNetworkHandler_AddNetworkQueue)
        ++UNetworkHandler_vftable;
    *UNetworkHandler_vftable = (void*)UNetworkHandler_AddNetworkQueue_hook;
    return 0;
}

BOOL WINAPI DllMain(HMODULE hModule, DWORD ul_reason_for_call, LPVOID)
{
    if (DLL_PROCESS_ATTACH != ul_reason_for_call)
        return 1;
    DisableThreadLibraryCalls(hModule);

    CreateThread(0, 0, &InitThread, 0, 0, 0);
    return 1;
}

Спасибо Demion за идею использовать __fastcall вместо __thiscall.